Thermoplastic coated filamentary member

ABSTRACT

This disclosure relates to a thermoplastic adhesive coated yarn or filament employed in the manufacture of boxing for upholstery and the like. The yarn or filament contains a uniform coating of a thermoplastic material which has sufficiently high viscosity to prevent the thermoplastic material from bleeding through the fabric to which it adheres at ordinary temperatures, and with viscosity low enough to permit coating of the filament or yarn uniformly at coating temperatures and such that a suffucient degree of melting will take place at the application temperature for the sticking of the thermoplastic adhesive to the boxing fabric. In a preferred embodiment of the invention, a rayon filament is coated with a layer of a polymer or ethylene, preferably an ethylene-butene-l copolymer, the copolymer has a molecular weight of less than 10,000, has dissolved therein and organic acid ester which produces a composition having a viscosity at 300* of 100,000 to 200,000 c.p.s., and a viscosity at 350* of less than 8,500 c.p.s. The preferred organic acid ester is ethyl palmitate.

United States Patent [72] Inventors Mich. [21 Appl. No. 683,821 [22] Filed Nov. 17, 1967 Nov. 23, 1971 Sackner Products, Inc. Grand Rapids, Mich.

[45] Patented [73] Assignee [54] THERMOPLASTIC COATED FILAMENTARY MEMBER 9 Claims, No Drawings [52] U.S.Cl 161/175 [5 l] Int. Cl D02g 3/36 [50] FieldofSearch 161/175 [56] References Cited UNITED STATES PATENTS 2,999,772 9/l96l Burk et al. 117/138.8 3.390.036 6/1968 Wright et al. 161/175 Primary ExaminerBenjamin R. Padgett Assistant Examiner- Brooks H. Hunt Attorney-Price, Heneveld Huizenga & Cooper ABSTRACT: This disclosure relates to a thermoplastic adhesive coated yarn or filament employed in the manufacture of boxing for upholstery and the like. The yarn or filament contains a uniform coating of a thermoplastic material which has sufficiently high viscosity to prevent the thermoplastic material from bleeding through the fabric to which it adheres at ordinary temperatures, and with viscosity low enough to permit coating of the filament or yarn uniformly at coating temperatures and such that a suffucient degree of melting will take place at the application temperature for the sticking of the thermoplastic adhesive to the boxing fabric.

In a preferred embodiment of the invention, a rayon filament is coated with a layer of a polymer or ethylene, preferably an ethylene-'butene-l copolymer, the copolymer has a molecular weight of less than 10,000, has dissolved therein and organic acid ester which produces a composition having a viscosity at 300 of 100,000 to 200,000 c.p.s., and a viscosity at 350 of less than 8,500 c.p.s. The preferred organic acid ester is ethyl palmitate.

THERMOPLASTIC COATED FILAMENTARY MEMBER This invention relates to coated thermoplastic filamentary members for upholstery boxing. In one of its aspects it relates to an article of manufacture for use in making boxing for upholstery comprising a filamentary member uniformly coated with a thin layer of a thermoplastic adhesive having a viscosity sufficiently low to coat the filamentary member uniformly at the coating temperature and to stick to the boxing fabric at gluing temperature, and sufficiently high enough to prevent the thermoplastic material from bleeding through the fabric at ordinary temperatures.

In another of its aspects, the invention relates to a method for making upholstery boxing comprising folding a strip of fabric along one edge over upon itself, positioning within the fold a welting cord, and adhering the fabric together to enclose the welting cord with a filamentary member coated with a thermoplastic material, the thermoplastic material of the coating comprising a polymer of ethylene, the coating having a viscosity in the range of 100,000 to 200,000at 300 and a viscosity less than 8,500 c.p.s. at 350 F.

In copending Ser. No. 579,722, filed Sept. 14, 1966, entitled WELTING METHOD AND APPARATUS, now abandoned there is disclosed and claimed a method and apparatus for making upholstery boxing. The boxing comprises a strip of fabric of predetermined width having at least one edge folded over upon itself, a welting cord positioned within the fold of the fabric, and the strip of fabric being glued together over the welting cord by a length of string containing a thermoplastic glue. The glue-containing string is positioned between the strip of fabric and the folded over portion of the strip a distance from the edge sufficient to accommodate the cord.

The thermoplastic glue used to coat the filament in this boxing must uniformly coat the filament. Thus the thermoplastic material must be sufficiently fluid to flow evenly over the filament surface and must adhere to the base material. The coating temperature is generally limited by the type of base filament or yarn and also by the decomposition temperature of the cooling material. When the base filament is made from rayon the coating is done about 350 F. Most thermoplastic glues containing a l -olefin polymeric base will adhere to rayon.

The thermoplastic glue must be soft enough to stick to the fabric and must have the ability to stick to synthetic fabrics at the gluing temperature which is generally about 275 to 325 Still further the thermoplastic glue must have sufficiently high viscosity at ordinary temperature so that it will not bleed through the fabric. Additionally, the glue must be soft enough to give a flexible welting seam. it is also desirable that the glue be sufficiently solid at room temperature so that the thermoplastic coated filament does not stick to itself on the spool before the gluing operation.

We have now discovered that a low-molecular weight ethylene polymeric base material modified with esters can be employed as the thermoplastic glue coating to provide a suitable glue which satisfies the above-listed prerequisites.

By various aspects of this invention one or more of the following, or other, objects can be obtained.

It is an object of this invention to provide a filamentary member coated with a thermoplastic glue for use in the manufacture of upholstery boxing, which filamentary member sticks to natural or synthetic fabrics at elevated temperatures without bleeding through the fabric at ordinary temperatures.

It is further object of this invention to provide filamentary members coated with a thermoplastic glue for use in the manufacture of upholstery boxing, which filament is uniformly coated with the thermoplastic glue, but which will not bleed through the fabric at ordinary temperatures.

It is a still further object of this invention to provide a thermoplastic glue coated filament which is soft enough at ordinary temperatures for providing a flexible welting seam in upholstery boxing and which has sufficient body so as to avoid bleeding through the fabric at ordinary temperatures.

A further object of this invention is to provide a filamentary member uniformly coated with a thermoplastic glue which thermoplastic glue is easily adhered to the fabric without bleeding through of the glue and without producing a hard welt seam.

It is yet another object of this invention to provide a method for making a boxing wherein a thermoplastic adhesive is used and in which boxing a flexible welting is made without bleed through of the thermoplastic adhesive at ordinary temperatures.

Other aspects, objects, and the several advantages of this invention are apparent to one skilled in the art from a study of this disclosure, the drawings, and the appended claims.

According to the invention, there is provided a coated filamentary member for use in making boxing for upholstery. The filament member is uniformly coated with a layer of a thermoplastic adhesive having a viscosity sufficiently low to uniformly coat the filament at the coating temperature, sufliciently low to stick to fabrics at the gluing temperature, and a viscosity sufficiently high to permit the thermoplastic coating from bleeding through the fabric to which it adheres.

The filamentary member can be any suitable material to which the thermoplastic glue adheres. It can be a single filament or a plurality of filaments would together to fonn a yarn. Preferably, the filamentary member is a yarn made from a spun synthetic cellulose material such as rayon. Tensile strength of the filamentary member should be less than 10 pounds so that it can be broken, if necessary, to avoid puckering of the boxing fabric. The yarn is preferred over a monofilament because the yarn tends to flatten out as it is compressed to give a flatter seam and a wider bond. A l6/2rayon yarn is an example of a suitable filamentary member.

The thermoplastic glue is preferably a low-molecular weight nonemulsifiable polymer of ethylene having a molecular weight of less than 10,000, preferably in the range of 2,000 to 10,000. The low-molecular weight polymer can be a copolymer of ethylene with other monomers copolymerizable therewith. Examples of the monomers which can be copolymerized with ethylene include propylene and butenel.

The thermoplastic base material is modified by organic esters to produce the proper viscosity adhesive. The organic esters are generally of the formula CH (CH ),,,COO(CH CH wherein m and nare numbers from zero to 16 and m and n is at least 10 Preferably, the organic esters used boil above 350' F. and do not decompose below 350 F. Examples of organic esters which can be employed include:

ethyl hendecanate methyl laurate propyl caprate propyl tridecylate ethyl tetradecanoate ethyl pentadecylate ethyl palmitate methyl palmitate propyl margarate ethyl sterate The preferred ester is ethyl palmitate.

The percentage of organic ester in the low-molecular weight polymer can vary widely depending on the type of ester used and the molecular weight of the polymer. The range will generally be from 1 to 50 percent ester based on the total weight of ester and polymer.

The ester and polymer are blended so as to produce a mixture having a viscosity of less than 8,500 c.p.s., preferably about 7,500 c.p.s. at 350 F. Also the viscosity of the thermoplastic mixture must be in the range of 100,000 to 200,000 preferably 170,000 to 180,000 c.p.s. at 300 F. The viscosity mentioned in this application relates to Brookfield viscosity.

EXAMPLE 1 A 16/2 rayon yarn was drawn through a bath of Fuller 4087* Hot Melt at a temperature of 350 F. The ther moplastic adhesive sticks to the rayon yarn and uniformly coats the yarn at that temperature. The viscosity of the thermoplastic material is 2,900centipoises at 300 and 1,300 centipoises at 350 F. The coated yarn was then cooled and wound onto a spool. At room temperature the coated yarn sticks to each other on the spool.

The thermoplastic coated yarn was employed in making upholstery boxing. A strip of material was fed into a boxing machine such that is disclosed in copending Ser. No. 579,722, filed Sept. 15, 1966 entitled WELTING METHOD AND AP- PARATUS, now abandoned. The thennoplastic adhesive coated yarn was heated to about 300 F. and was placed between the folded over portion of the material and the underside of the material. A welting cord was placed within the fold. The fabric was pressed together on either side of the coated yarn to adhere the two portions of the fabric together. The glue stuck to the material and held it together. After a period of time, the fabric was heated to about 100 F. The thermoplastic glue began to bleed through the fabric.

*Fuller No. 4,087 Hot Melt is a synthetic resin base material used for adhesives and is manufactured by H. B. Fuller Co.

EXAMPLE 2 The same rayon yarn used in example 1 was coated with a thermoplastic adhesive identified as Franklin Compound No. 4270 by drawing the rayon filament through a bath of the thermoplastic adhesive at about 350 F.

*The compound 4270 is an ethylene copolymer resin modified by natural and synthetic resin, esters and has a viscosity of 11,000 c.p.s. at 350 F. and 250,000 c.p.s. at 300 F. The compound is manufactured by the Franklin Glue Co. of Columbus, Ohio.

The coated yarn is cooled and rolled into a spool. The thermoplastic adhesive does not coat the rayon yarn uniformly. The coated yarn does not stick together on the spool.

The coated thermoplastic yarn is employed in making boxing as above described in example 1. In this case, the thermoplastic coated yarn is heated to about 300 and pressed between the fabric. The adhesion is good, but due to the uneveness of the coating, the seam is discontinuous in certain portions.

The boxing produced by the operation does not show any bleed through of thermoplastic material when heated to 100 F. However, the glued seam is hard in spots due to the hardness of the thermoplastic material and the unevenness of the coating.

EXAMPLE 3 A third glue composition is prepared by blending the glue of example 1 with the glue of example 2 until the blend had a viscosity of about 175,000 c.p.s. at 300 F. and about 7,500 c.p.s. at 350 F. The molecular weight of the polymer is less than 10,000.

A rayon yarn of examples 1 and 2, is coated with this blend of thermoplastic adhesive by drawing the same through a bath at 350 F. The coated filament is cooled and wound onto a spool. The filament on the spool at room temperature does not tend to stick to itself on the roll.

The coated filament is heated to 300 F. and employed in making boxing as above described in examples 1 and 2. The thermoplastic material is uniformly coated onto the filament and produced a continuous glued seam in the boxing. Further, the seam is soft and flexible and the thermoplastic material does not bleed through the fabric when the fabric is heated to 100 F.

The thermoplastic glue material of example 3 has been found to adhere to all types of synthetic and natural fabrics.

The thermoplastic filament can have a smooth surface or a fuzzy surface, the latter of which would be present in yarntype filaments. A fuzzy type of yarn would give a plurality of bonding points for a stronger bond between the fabric and the glue coated filament.

In the event that there is any puckering of the fabric during the boxing operation, the fabric can be pulled apart to break the yarn without danger of pulling the fabric. in other words, the seam can be opened in various places easily with the use of the thermoplastic glue coated filament. Thus, the use of the thermoplastic coated filamentary member provides an easy solution to the puckering problem.

The filament can be circular in cross section, or can be oval, or any shape in cross section. If it is desirable to give a wider area of adhesion, the filament can be oval in cross section to give this result. Further, the adhesive can be incapsulated on the filament if desired whereby the incapsulation, is broken when the filament is heated and/or pressed against the fabric.

Also according to the invention, there is provided a method for making boxing which comprises folding a length of material over upon itself, feeding a welting cord between the fold of material heating the thermoplastic coated filament to a temperature in the range of 275 to 325 F., and positioning the heated thermoplastic glue coated filamentary member adjacent the welting cord and between the layers of fabric, the thermoplastic glue coated filamentary member having a viscosity in the range of 100,000to 200,000 c.p.s. at 300 F. and a viscosity less than 8,500 at 350 F.

The thermoplastic glue coated filamentary member comprises that article which has been hereinbefore described with reference to the first embodiment of the invention.

The use of the ethylene polymeric thermoplastic material gives a glue which does not discolor upon heating. Further, the glue does not decompose when heated to the coating or bonding temperatures.

Reasonable variation and modification are possible within the scope of the foregoing disclosure, the drawings, and the appended claims of the invention without departing from the spirit thereof.

We claim:

1. An article of manufacture comprising a filamentary member uniformly coated with a thin layer of thermoplastic adhesive having a viscosity sufficiently low to coat the filamentary member uniformly at a coating temperature and sufficiently low to stick to fabrics at a gluing temperature lower than said coating temperature, the viscosity of the thermoplastic adhesive being high enough to prevent bleed through of the thermoplastic adhesive at ordinary temperatures, said thermoplastic adhesive being a low-molecular weight polymer of ethylene containing an organic ester to control the viscosity of the adhesive.

2. An article of manufacture according to claim 1 wherein said filament is rayon yam having a tensile strength less than about 10 pounds.

3. An article of manufacture according to claim 1 wherein said thermoplastic adhesive has a viscosity in the range of 100,000 to 200,00 c.p.s. at 300 F.

4. An article of manufacture according to claim 3 wherein said thermoplastic adhesive also has a viscosity less than 8,500 c.p.s. at 350 F.

5. An article of manufacture according to claim 1 wherein the viscosity of said thermoplastic adhesive is less than 8,500 c.p.s. at 350 F.

6. An article of manufacture according to claim 1 wherein said thermoplastic adhesive has a viscosity in the range of 170,000 to 180,000 at 300 F. and a viscosity of about 7,500 c.p.s. at 350 F.

7. An article of manufacture according to claim 1 wherein said polymer of ethylene comprises an ethylene monomer copolymerized with a higher 1 -oelfin to provide a polymer having a molecular weight less than 10,000.

8. An article of manufacture according to claim 7 wherein said thermoplastic adhesive has a viscosity in the range of 100,000 to 200,000 c.p.s. at 300 F. so that said adhesive sticks to fabrics at a gluing temperature lower than said coating temperature, the viscosity of the thermoplastic adhesive being high enough to prevent bleed through of the thermoplastic adhesive at ordinary room temperatures.

P0405J UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION patent 3,622,438 Dated November 23, 1971 Inventor) David H. Esler, Frank J. Hormuth, Jack C. Corcoran,

Jerry M. Markley It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 5;

"3502F." should read 350F.

Signed and sealed this L .th day of July 1972.

(SEAL) Attest:

EDWARD MJ' LETCHERJR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

2. An article of manufacture according to claim 1 wherein said filament is rayon yarn having a tensile strength less than about 10 pounds.
 3. An article of manufacture according to claim 1 wherein said thermoplastic adhesive has a viscosity in the range of 100,000 to 200,00 c.p.s. at 300* F.
 4. An article of manufacture according to claim 3 wherein said thermoplastic adhesive also has a viscosity less than 8,500 c.p.s. at 350* F.
 5. An article of manufacture according to claim 1 wherein the viscosity of said thermoplastic adhesive is less than 8,500 c.p.s. at 350* F.
 6. An article of manufacture according to claim 1 wherein said thermoplastic adhesive has a viscosity in the range of 170,000 to 180,000 at 300* F. and a viscosity of about 7,500 c.p.s. at 350* F.
 7. An article of manufacture according to claim 1 wherein said polymer of ethylene comprises an ethylene monomer copolymerized with a higher 1 -oelfin to provide a polymer having a molecular weight less than 10,000.
 8. An article of manufacture according to claim 7 wherein said thermoplastic adhesive has a viscosity in the range of 170,000 to 180,000 c.p.s. at 300* F. and about 7,500 c.p.s. at 350* F.
 9. An article of manufacture comprising a filamentary member uniformly coated with a thin layer of thermoplastic adhesive having a viscosity of less than 7,500 c.p.s. at 3502* F. so that said adhesive coats the filamentary member uniformly at a coating temperature and having a viscosity in the range of 100,000 to 200,000 c.p.s. at 300* F. so that said adhesive sticks to fabrics at a gluing temperature lower than said coating temperature, the viscosity of the thermoplastic adhesive being high enough to prevent bleed through of the thermoplastic adhesive at ordinary room temperatures. 